Fusible link



Apr. 24, 1923."

H. M. NACEY y FUSIBLE LINK Filed May 9 Apr. 24, i923., 1,452.522 H. M.NACEY FUSIBLE LINK Filed May 9, 1919 2 sheets-sheet 2 Patented Apr. Z4,1923. i

Y H ARRY M. NACEY, 0F CHICAGO, ILLINOIS.

Applicationv inea- May 9,1919. seriai 110.296,036.

T0 all whom t may concern:

Be it known that I, HARRY M. NACEY, a citizen of the United States, anda resident of Chicago, in the county of Cook and State oflllinois7havejinventedcertain new and useful Improvements in Fusible Links, ofwhich the followingfis a full, clear, andexf act specification.

This invention relates vto improvements in fusible links adapted for usein connection with automatic heads for sprinkling systems Hand forfire-proof doors, shutters and windowsfor retaining them in their openposition, in which heretofore a ,fulcrum' block ...has been .enclosed bya chamber betweenA and formed from the `platesisolating thefulcrum'block from `the solder securing the plates together, the ysurfaces of'which fulforumv block are parallel throughout and in theiroperativev position normally extend at an oblique angle withthe planefofthe sur- .facesofthe plates with their flat longitudinal edges seatedagainst the shoulders substantially parallel therewith, yformed in theopposing plates.

vThese 'fulcrum blocks are 4.intended to fa` -cilitate the separation ofthe plates on the melting ,of the solder, Afollowing the force of a pullor pushing-thrust, as may be, to which the plates are ksubjected intheir operative position. In practiceit is found, however, that theplates do not separate with desirable quickness from either of theseforces 'because of ythe .pinching ofthe fulcrum block against,its'angular seats and .the dragging friction between the plates; lthata fusible link so constructed is substan- `tiallylinoperative when, byraccident ordesign,vr the space between the opposingsurfaces of thefulcrum block and the .plates becomes filled .with solder; that in theAabsence of thesolderingthe fulcrum .block to both plates, following,the vcommonpractice of sweating them together, the strength ofadherencejbetween kthe plates isinsufficient for obtaining the bestresults. l i The `prime object. of .my invention, broadly stated, is toprovide a fusible link with a yfulcrum block, they construction of whichand its location between .the plates ,of the link is suchy that onl the`melting, ,ofl the ,y solder the Vplates will have a rolling movementionthe .fulcrum vblock facilita-tingfthey jseparation of the plates-7*oreventinga dragv respectively and 4.

ging friction between the plates and the ulcrum block from pinchingagainst their seats, and a means by which it is possible and practicalto soldery the block to the plates and accordingly stiii'enandstrengthen the plates against accidental detachment.

More kspecifically stated, the object of my invention isa fusible linkprovided with a fulcrum block and opposingk curved bearing surfaces, oneof kwhich surfaces is convex and kthe other concave with the yfulc'runublock and plates of the link soyarranged with reference to each otherthat on the melting of the solder theplates are quickly .laterallyseparated. by a rolling frictional force, preventing the ends of theblockimpinging against and drag friction between the-plates, andproviding for soldering the plates to .the surfaces of the block intheir entirety, land accordingly increasing the eX-.

tent ofthe soldered surfaces of the plates `and reducing the liabilityofthe plates to accidental separation. i

With these' ends in view,'my'1nvention nds embodiment in certainfeatures of-novelty in the construction, combination and arrangement ofparts `by which .the objectsl and certain other objects are attained,all

as .hereinafter fully described with refer-r 'A vence to theaccompanyingdrawings,- .and more particularly pointed out inthe claims.

11,1 said drawings:

Fig. l illustrates a longitudinal lsection taken on the line 1,41, ofFigs. 10t and 11, a fusible linkof :the pushing-.thrusttypd in Awhich myinvention-finds its embodiment. Fig.. 2 is asimilar view taken onfthesame line of a modification.

Fig-.8 is a similar -view takenkon thesame. llineof a furthermodification of the fusible -link shown injFig. 1.' n

Fig.. 4 is a longitudinal .sectional view taken on the lines 4 4 ofFigs. f1.2 andfl of a fusible link ofthe construction shown-- i -in Fig.1 ofthe l'type which are pulled open.

Fig. 5 is a modification of the pull type shownin Fig. 4taken` onthesameline.' l

Fig. 6 isa similar view yofa further modification taken on the same lineas Figs. 4;

Fig. `7 illustrates Iin `perspective theifulcrum block forthe'link'.shown Figs. 1

Fig. Sis* a .oflthefulcrum block for the links shown in Figs. 2 and 5.

Fig. 9 is a similar view of the fulcrum block shown in Figs. 3 and 6.

Figs. 10 and 11 are external plan views of the opposing plates forfusible links of the push-thrust type shown in Figs. 1, 2, and 3, and

Figs. 12 and 13 are similar views of the opposing plates shown in Figs4t, 5 and 6.

All of the fusible links shown in Figs. 1, 2, 3, 10 and 11 are of thecompression type, that' is to say, their plates, 141 and 15, in theiroperative position are subjected to an endwise compressive force foreffecting their separation on' the melting of the solder normallysecuring them together, which plates are preferably provided toward oneend with a recess, 16, for the reception of a curved depressed endportion, 17, opposed thereto, for aligning the opposite ends of the twoplates so that the longitudinal stresses will not normally tend toseparate the plates.

The plates, 14 and 15, are severally constructed from phosphorus bronze,brass or steel and, as shown in Figs. 1, 2 and 3, are provided withrespective recesses. 18 and 19. forming a chamber in which is confined arectangular fulcrum block, 20, which fulcruin block in Fig. 1 isprovided tra-nsverselywith opposing convex surfaces, 21, 21. adapted tofit in and against correspondingly concave bearing surfaces, 22, 22, inthe plates, the upper and lower edges, 23, 23, of which blocks areopposed to but slightly separated. from angular seats, 24. 2.4., formedin the plates and in slightly; inclined parallel arrangement, so that oncompressing the links following the melting of the solde-r the plateswill have a rolling movement on the opposing convex surface of thefulcrum block for quickly forcing them apart and in the absence of theleast amount offriction consistent therewith.

For example. the. opposing convex surfaces for the fulcrum block may belimited in their location at the upper end of the fulcrum block, 25, 25.shown in the modification in Fig. 2 and opposed by concave bearingsurfaces 26. 26, formed in the plates, but whenso located the lowerstraight edge, 27, of the fulcrum block should be quite close to, if notseated against. the shoulder, 28, in the plate, 14, so that on themelting of the solder the plates will have. a rolling movement on thecurved surfaces at the upper edge of the fulcrum block, operating toquickly separate them by a rolling movement in the absence of a draggingfrictional resistance. f

` As a further modification, the fulcrum block, 20. in Fig. 3 isprovided at both ends wit-h convex curved surfaces, 29. 29. so thatfollowing the melting of the solder with the llink under compression theplates are separated on the melting of the solder by la rolling movementon both ends of the fulcrum block for `compelling the separation kof theplates yin the absence of dragging friction.

The fusible links shown in Figs. a, 5, 6, 12 and 13 are of the pull typeand for this purpose do not materiallyT differ in their constructionfrom what has been described other than that both plates are providedtoward their extremities with openings. 30, for their connection withthe struts of automatic sprinkler heads or with the chains for holding`a fire-proof sash, door, et cetera., open, and wherein the link issubjected to a pull at both, of its ends in opposite directions. Otherthan being of the tension type. the plates 31, 32, in Fig. 4t and thefulcrum block, 33, correspond with the construction and arrangementshown in Fig. 1.

In Fig. 5 the plates 34.-, andthe ful-v crumblock, 20, likewisecorrespond in construction and arrangement with the fusible link shownin Fig. 2, as does also the plates 36, 37, andthe fulcrum block, 38,correspond in construction with the fusible link shown in Fig. 3. 'thefulcrum block in Figs. 1 and 4- being shown in perspective in Fig. 7,the fulcrum block in Figs. 2 and 5 being shown in perspective in Fig. 8,and the fulcruni block in Figs. 3 and 6 being shown in perspective inFig. 9.

llt is now to be observed that the fulcrum blocks and the chambers inwhich they are confinechshown in Figs. 1, 3, 11, and 6, are

located in a plane at an oblique angle to the plane of the opposingsurfaces of the plates between which they are confined; that in Figs. 2and 5 the greater part of the fulcruin block lies in a plane parallelwith the adiacent opposing surfaces of the plates. with the center fromwhich the curved end is struck up located in the plane with that of thekopposing fiat surfaces of the plates; and that notwithstanding thedifferences and location of the curved surfaces and their arrangementrelative to the opposing plates between which they are confined, theseseveral fulcrum blocks, in every instance, whether of the push or pulltype, operate as curved cams opposed to concave bearing cam action forforcing the plates apart it'j is not only possible but practical tosweat the plates to and throughout the surfaces of the fulcruniblock ofmy invention Aand accordingly increase the strength. and clurability ofa fusible link as a Whole, and prevent the liability of the accidentaldetachment when both in and out of operative position.

l claim and desire to ent is:

l. A fusible link, comprising iiicombination a pair of plate members,each providedwithl an elongated concave surface directly kopposed toeach other, and' a ful- 'cruin block provided with convex surfacesi'forresponding` with and adiacently confined` `and adjacently opposedto said surfaces,

which said block is located yin a plane at an oblique angle to.r theplane of` said'plate finembers.

' 3. A fusible link, comprising in combination opposing fiat plateJmembers respec- -tively provided withelongated concave surfaces directlyopposed to eachother, and' an angular fiat fulcrum block provided withconvex surfaces conforming toand directly opposing the concave surfacesin said plate members.

4. A fusible link, comprising in'combina tion opposingl flat platemembers respec-k tively provided ivith elongated concave vsurfacesdirectly opposing each other, and

fiaty angular fulcrum block, provided with convex surfacesconforming toand directly opposing the concave surfaces of the plate members Whichsaid blocks extend obliquely to the plane of said plates. Y

5. A fusible link, comprising in combination 4flat .angular plate,lmembers, respectively provided' With directly' opposing elon-y gatedcurvedsurfaces, a fulcrumfblock provided vvith convex surfacescorresponding VWith and located adjacent said concave surfaces, and athin ilmof solderbetiveen andy Having thus described invention, whatsecure by Letters Platuniting said surfaces in their operativepo sition.A l i r 6. A fusible link, comprising in combination flatvplate members,respectively opposing each other, .provided With elongated concavesurfaces registering with eachother, 4

Vanda flat angular fulcrum block the oppoi '60 convex surface'respectively correspondingv vWith and proyectinginto said'concavesursite sides of which are each provided With a faces, and a thin lm ofsolder locatedbetween and `unitingsaid surfaces in their..

operative position. v

7; A fusible link, comprising incombination atplate members,respectively oppos-k ing each other, provided with elongated concavesurfaces registering with veach other, a flat angular .fulcruni block`the opposite l sides of which are each provided with a convex surfacerespectively corresponding With .and projecting into said concavesurfaces,

and a thin film of solder locatedbetwcen and uniting said surfaces intheir operative position, said .fulci'umblock being located to extend atan obliqueangleto the plane of said plates.V p

Inv Witness whereof, I have hereunto set myhand and affixed my seal,this th day of April,"A. D. 1919.

l HARRY MQNACEY. :Witnesses:

MABELKATZ,

